Superfluid signatures in magnetar seismology

TL;DR

This paper explores how neutron star superfluidity significantly influences magnetar oscillations, suggesting that superfluid effects are crucial for accurate magnetar seismology and can potentially reveal properties of supranuclear matter.

Contribution

It demonstrates that neutron superfluidity has a more significant impact on magnetar oscillations than crustal magnetic fields, highlighting its importance in seismological models.

Findings

Superfluid imprint exceeds crustal magnetic field effects.

Superfluid presence affects oscillation dynamics.

Superfluid components are essential for accurate magnetar seismology.

Abstract

We investigate the role of neutron star superfluidity for magnetar oscillations. Using a plane-wave analysis we estimate the effects of a neutron superfluid in the elastic crust region. We demonstrate that the superfluid imprint is likely to be more significant than the effects of the crustal magnetic field. We also consider the region immediately beneath the crust, where superfluid neutrons are thought to coexist with a type II proton superconductor. Since the magnetic field in the latter is carried by an array of fluxtubes, the dynamics of this region differs from standard magnetohydrodynamics. We show that the presence of the neutron superfluid (again) leaves a clear imprint on the oscillations of the system. Taken together, our estimates show that the superfluid components cannot be ignored in efforts to carry out "magnetar seismology". This increases the level of complexity of the modelling problem, but also points to the possibility of using observations to probe the superfluid nature of supranuclear matter.